Lathe dog



April 1950' J. M. ROLLAND 2,505,007

LATHE DOG Filed May 3, 1946 s Sheets-Sheet 1 FIGURE l- I NV EN TOR.

JOHN'M. ROLLAND ATTD RN EYS April 25, 1950 J. M. ROLLAND 2,505,007

LATHE DOG Filed May a, 1946 3 Sheets-Sheet 2 FIGURE 2 FIGURE 6 I N VEN TOR.

JOHN M. ROLLAND A'I'I'D R N EYE J. M. ROLLAND April 25, 1950 LATHE DOG 3 Sheets-Sheet 3 Filed May 3, 1946 FIGURE 3 FIGURE 4 IN VEN TOR.

JOHN M. ROLLAND ATTDRNEYB Patented Apr. 25, 1950 UNITED S ATES OFFICE 3,505,607- LAT Thee JehnM- .tte d; Ghiee a 1 Application May-;3, 194 Serial No. 667,096

he nt eh -inveht eh r la es te imp vemen in lathe dogs or work holders of the. type enlpleyett ro r met I, we lti s mach n to aha.i e in a plh alityht ra ia l r pt eeb e the. work he d e Jews tewerk ha they b slight y fi enten In, arryin hut-my ny htieh th e -e92 :ta hed ae is equ npeii with en. operat handwh a d means a e nre ided for t h ti th rotary mov ment a the an he l into rad ll r inmeab movement of a y shrew he f r pro ect ng an ret ct ng the jaws mountedupon the bolts,

B h ht l zatie o m n ehti ninv h ,meehaaiee uctur at h ,do h i w kho clin via smawith h en eheeb eui kly e ter u and w t l que eei ity the Je ma be t te o e ease the wothhfter tQlhh t h' f th u ning p ration, thhsse ing. tim and labor. espethe 1 9s h eele he-[ nventi n consis sin eet ai novel t mhihetiehsand arrangem nts-hf. p use -w ll hereineft he mere hil y set-f rt and l imed.

h cc mpa yi g drawings .1 hav illustrated one completeexa pple of the physical em bpdirnentoj my invention wherein the parts are combined and arranged in accord with one mode I have thusiar devised forthepractical application of the principles of my invention, but it will be understood that changes and alterations may be made in these exemplifying drawings and mechanical structures within the scope of my claim without departing from the principles of the in ent-ten,-

ifisi re 1 vertical, lon itudinal-3 sectional,

view hlz i sh.v the. est mates myw-mvention, attached to the face plate of a rotary lathe, and showing the work to be turned by the lathe.

Figure 2 is a rear face view orelevation of the dog, as at line 2-2 of Fig. 1, partly broken away for convenience of illustration.

Figure 3 is a fragmentary view, with some parts in section, as at line 3-3 of Fig 1.

Figure 4 is a detached detail view showingthe relation between the gear ringof the hand Wheel cr e -eel 2 --ehd one, at the sea he utiliz d in teeter?- e o theiew b ts F 5 is a detail, perspective view of one of t wer krclamn ne. Jew an His-tire 5 is we perspective ie of one Qt the Qui k de eeh hl spri e e s o e i re aining, workc amp n j w on it lt- In o her h t e utility f the appl nce i e a ente a etary la he he read ly be un e tood I ave hown-e p ieh of a s a da d th cen er n udin a tu a spindle s and te ih ri h and the cir ular f l e F, t e with the work tobe turned as W, all mounted to revolve or rotate in conventional manner, and with h work W pr e l cer d- 'l'he u ual tee p ate F s drilled o ei ha ts. by means at hi h e of different size he tt ehett and th me ha l t uethr ilt tfltitl the the e m unt d as e gripping-unit FPO-I1: the teee Plate The dog is attached to the face plate through the-m d um eta eireul o n n r e pn' e or body 1., when is rigidly fixed on the outer I teet ring we ni -terr m n f s o ts p Allen screws Zthreaded into the face of the raceplate The annular base-plate, which is arranged 1. Qt e t e v ash ne i. o i te r h u n er ee xe 3 and 4, the outer open ends 91, which are closed by co er p at s fastened b sc ws or bo 'Ihese housings form gear boxes that are provided, with required openings in their walls to accommodateoperat n p r of d d t I number of housings :varieswith the number of work holding clamps oft-he dog, two of which are illustrated herein.

The housingsorgear boxes provide the supports for two diametrically arranged work gripping jawsv fi and 1' of identical structure, each havingan inner concave or angular gripping face for contactwith-the cylindrical work W, and the jaws are adapted" for-radial adjustment toward 1 the axial eenteroffthelathe togrip thework, as well as for-radial retracting movement to release theworkfrom the dog after completion of a. turning operation.

v ASH indicated especially in Fig. 5 each jaw is gfashioned with a round socket 8 opening through its inner face and bottomed with a square recess 8', to receive a reciprocably mounted, rotary, ,screw bolt 9, that isprovided at its inner end with an annular exterior groove in and a squared l portion II). The recess 8 receives the portion f wall of the housing 3.

l and thereby locks the screw bolt 9 against rotation.

The jaws are retained on their bolts, by means of U-shaped spring detents H, the two arms of which are compressed for insertion through a slot l2 in one side of a jaw. After being guided through slot 12 the arms of the spring detent embrace the grooved bolt, and then spread, slightly into an enlarged interior annular slot [3 of the socket 8, thus locking the bolt 9 against longitudinal displacement from the jaw, causing the jaw 6 to be projected or retracted with its respective bolt 9.

The jaws may quickly be detached from the bolts for substitution or replacements by first withdrawing the spring detents from the grooved bolts and the jaws.

As best seen in Figs. 1 and 3, each of the bolts 9, 9, extends radially through an aperture M in the inner wall of the housing and it also projects through an alined hole in the removable cover plate of the housing, the bolt being externally threaded for a major portion of its length where it passes through the housing or gear box.

Each externally threaded bolt is threaded within an internally threaded bushing or flanged sleeve I5 slidably mounted within the gear box cover 5, and an equalizing spring 16 is coiled about the bolt 9 and interposed between an exterior end cular base .plate I; an annular collar 24 being fixed to the circular base plate between the face plate F and the bearing plate 2|.

To complete the hand wheel an exterior spoked ring 25 is bolted at 26 to the plate 2!, which ring projects beyond the periphery of the face plate F, and the housings where it is readily accessible for turning the hand wheel to operate the work clamping jaws.

Rotation of gear ring 20 rotates sleeve [5 to force bolt 9 and its jaw 6, towards the work W to grip the same. Upon reverse rotation, the jaws flange of the bushing l5 and an inner seat of a The spring 16 of each bolt 9 provides a self-centering means for the work clamping jaws by retaining the same from I dropping toward the work W.

The bushing performs the functions of a traveling, rotary, nut for projecting and retracting the reciprocable bolt 9, and the bushing is retained i in operative position by co-action of its upper end flange with an enlarged head I! of the screw bolt, which parts are located exterior of the housing.

The exterior cylindrical surface of the bushbetween the cover plate 5 of the housing and the hub of the pinion or gear. An annular bearing support assists collar 20 to retain the gear is in operative position.

By this arrangement of parts it will be apparent that the rotation of the pinion or gear wheel is carries with it the bushing l5, which *pe1f0rms the functions of a nut to reciprocate the threaded bolt 9, for the purpose of adjusting its jaw 6 toward and from its work.

Each of the screw bolts is provided with a bushing and gearwheel and the two gear wheels are turned in the same directions through the instrumentality of asingle gear ring 20 that is mounted concentrically of the axis of the lathe, and rigid with a hand wheel that includes an annular bearing plate 2|, flanged near its outer periphery at 22 to provide an annular cover for the gearing, and also flanged at its inner periphery to provide a bearing'23 journaled on the cir- 6 are separated from the work W, permitting its removal, and the springs 56 assist in the jaw separation by forcing sleeve I5 axially of pinion l9. Even though the turning force is removed from ring 25, the spring i B by acting upward on sleeve !5 retains the bolt 9 from dropping down towards the center.

, Various changes and alterations may be made in the disclosure of my invention, within the scope of my appended claim.

' Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is:

In a lathe dog the combination of a face plate adapted to be attached to a lathe spindle, a base plate secured to said face plate and having an annular bearing portion, a plurality of gear housings circumferentially spaced on said base plate, a flanged sleeve rotatably and axially slidably supported by each said gear housing, internal threads in said sleeve, a screw bolt extending radially of said base plate and in said sleeve threadedly engaging said internal threads, a gripping jaw anchored on an end of said screw bolt and movable therewith, external splines extending axially on said sleeve, a pinion in each said gear housing and slidably mounted on each said sleeve, said pinion having grooves slidably receiving said external splines, means in each said gear housng forming a bearing support for each said pinion for rotatably supporting the same for movement in a fixed plane, a compression spring about said screw bolt, the ends of said spring engaging said sleeve and said gear housmg, respectively, biasing said sleeve axially of said gear housing, a manually-operated ring portion rotatably journaled on said bearing portion bel tween said face plate and said gear housings, and

a ring gear on said ring portion facing said hous- 'ings and meshing with said pinions whereby the latter are rotated by said ring gear for reciprocating said screw bolts to radially adjust said I jaws relative to said face plate.

JOHN M. ROLLAND.

REFERENCES CITED The following references are of record in the file of this patent:

- l Number- 1 UNITED STATES PATENTS Name Date 403,589 I Higgins May21, 1889 919,536 Carter Apr. 27, 1909 1,445,818

Barker Feb. 20, 1923 

